REPORT ON MATERIALS FRONI THE RORTNC^S AT FUNAFUTT ATOT>L. 241 



with a considerably larger quantity of corals, wliicli give a distinctive feature to the 

 cores. The corals are casts only ; they are very imperfectly preserved ; in some the 

 structiu'es are dissolved away, leaving vacant spaces ; in others the corals are replaced 

 with crystalline dolomite, which likewise fills up the calices, &c. In many instances 

 the corals appear to be in the position of growth. They include PoctUojJora, 

 Hydnophora, OrhiceUa, and other undetermined Astrsean genera, Cycloseris, 

 T'urhinaria, and Poyites. Of the foraminifera the most prominent is Folytrema 

 planum, which encrusts small corals and other organisms, forming nodules up to 

 50 millims. in diameter. Other genera present are Orhitolites, Haddonia, Textularia, 

 Glohigerina (rare), Carpenteria, Gypsina, Amphistegina numerous, Heterostegina, 

 and Cydodypeus. Alcyonarian spicules, Serpida, casts of Cliona borings, Hcdimeda, 

 and Litliothamnion. 



Details. 



(32a). Length 94 millims. Greyish, hard, very porous dolomite. Prominent nodular lumps of 

 Pohjtrciim planum, Amjjhistegina, Heterodegina, very large and numerous, mainly composing the coi'e. 

 Small perforate corals not determinable. Cheilostomatous polyzoa. 



(33a). Length 88 millims. Greyish-white, and very porous. Large nodules of Fohjirema 2)lanuvi, 

 the core almost wholly of this form, with Amplmtegina, Heterostegina, and probably Cyrlodypeus. 

 Casts of Pocillopora, in position of growth ; Ct/doseris (?) and another fungid coral. 



(84a, 35a). Total length 161 millims. Greyish, hard, very porous. Same characters as in the 

 preceding ; large nodules of Pohjtrema, with other foraminifera. A very neat cast of Hydnophora 

 microcona, Lam., apparently in position of growth. 



(36a) [691]. Length 97 millims. Whitish, hard, porous dolomite. Under the microscope there 

 is shown a considerable amount of apparently structureless sediment, cemented by crystalline 

 dolomite. Cast of perforate coral, not determinable, the structure replaced by dolomite. Haddonia, 

 Poli/treuia, Amphistegina, and Heterostegina ; the structure of these forms partly destroyed. Some detached 

 alcyonarian spicules. Halimeda. 



(37a) [692]. Length 100 millims. Greyish, hard, porous, and cavernous. About one-half the 

 core consists of an Astrsean coral, cf. OrhiceUa acropoi-a, Linn., either as hollow casts or infilled with sediment 

 and crystalline dolomite. The coral perforated by winding annelid C?) tubes with thick walls. 



(38a). Length 98 miUims. Whitish-grey, hard, porous to compact. Casts of OrhiceUa and 

 Pmites (?). The larger part of core apparently of fine detrital sediment, with undulating layers of 

 Polytrema and Lithothamnion. Ainphistegina and Heterostegina very indistinctly shown. Tubes with 

 thick walls. 



(39a). Length 105 millims. Greyish- white, hard, porous in places, also cavernous. Largo 

 specimen of OrhiceUa acropora (1) as cast. The coral structure has disappeared, the calices, infilled by 

 dolomite, now project as solid fluted pillars with vacant spaces between each. Casts of Porites and 

 PociUap&ra. Corals overgrown by Polytrema pAanuiu. Cast of shell now occupied by infilled Cliona borings, 

 which appear as small rounded beads linked together. Amphistegina. 



(40a) [693, 694]. Length 88 millims. Greyish, with white patches, hard, only just scratched 

 by knife, mostly compact. Larger part of core consists of cast of Porites, now for the most part infilled 

 solid by crystalline dolomite. Also cast of small Astrsean ; cf. OrhiceUa heliopora, Lam., sp. Outside the 

 corals much opaque sediment, with bands of Lithothamnion. Foraminifera indistinct, not numerous; 

 Gypsina, ■ Glohigerina (1), Amphistegina, and Heterostegina. Tubular boiings in coral, now infilled with 

 consolidated mud. Halimeda. 



2 I 



